Test fixtures are used in association with downhole tools during the uphole testing of the downhole tools. One such downhole tool is a downhole power unit. A downhole power unit is an electro-mechanical device that is designed to produce a linear force for setting (or pulling) wellbore tools such as monolocks, bridge plugs, packers and the like. A shaft extending axially from the end of the downhole is utilized to transmit this force. The downhole tool is tested uphole prior to insertion downhole to calibrate the tool and ensure that the tool can exert the appropriate amount of force via the shaft as required for a particular application, such as, for example, setting a packer having a 60,000 lbf activation threshold.
During these tests, using shear pins, the test fixture is attached to the end of the rod extending from the downhole tool. An axial force is applied to the test fixture via the rod until the shear pins fail. As a result of the high testing forces imposed on the test fixture by the rod, the test fixture is forcibly expelled from the downhole tool at a high velocity. Likewise, portions of the shear pins are separated from the test fixture during the process. Both the separated text fixture and the shear pins can present danger to personnel in the area of the tests.